As the lights dim for the opening scene of Nina Raine’s “Tribes” at La Jolla Playhouse, a recording plays of an orchestra tuning up — that multisonous dissonance of individual instruments finding their individual voices so they can unite in harmony.

But the trouble with the characters in the powerful and tonally rich drama that opened Sunday in the Mandell Weiss Forum Theatre is that they’re each so focused on their own music, they can’t hear anything or anyone else around them.

The Playhouse production reunites the off Broadway cast and director for the Drama Desk Award-winning play. Grippingly directed by David Cromer and led with a star-making performance by charismatic actor Russell Harvard, it’s the story of a hearing family who don’t know how to listen, and their deaf son, who’s desperate to be heard.

Christopher and Beth are middle-aged British novelists and intellectuals uncomfortably sharing their home with their three adult children — Daniel, struggling with both mental illness and his master’s thesis on language; Ruth, a lonely, aspiring opera singer who craves her disinterested father’s attention; and Billy, who was born deaf and catches what little he can from his family’s fractious dinner arguments by lip-reading and speaking aloud.

Christopher, a self-adoring snob with no filter, refused to teach Billy sign language because he feared it would label his son as “deaf,” which he crudely calls the “f---- Muslims of the handicapped world.”

Billy is content within the sheltered bubble of his eccentric family until he meets Sylvia. A hearing-impaired child of deaf parents who teaches him sign language, introduces him to others in the deaf tribe and helps him find a job. They move in together, and soon an emboldened Billy angrily challenges his family to learn sign language or he’ll never speak to them again.

Cromer’s fascinating direction plays with language on many levels. To translate sign language, French opera, Daniel’s growing stammer and even his and Billy’s unspoken thoughts, there are supertitles projected in multiple locations around Scott Pask’s meticulously detailed set. Daniel Kluger’s evocative sound design hints at Billy isolation from both the ugliness and the beauty of voices and music. The script is thought-provoking and it builds beautifully to a big payoff in the second act.

As Billy, Harvard (who was born deaf and speaks and signs) is mesmerizing to watch as the sweet but heartbroken man-child who’s aching to find love, purpose and a place in the world. Meghan O’Neill is compassionate but emotionally brittle as Sylvia, who loves Billy but is consumed by her own grief that she, too, is going deaf.

As Daniel, Thomas DellaMonica devolves from manic to barely functioning when his “mascot,” Billy, moves out. Dina Thomas is whiny and self-absorbed as Ruth. Jeff Still is pompous and insufferable as Christopher. And Lee Roy Rogers is the loving but smothering parent, Beth.

The two-and-a-half-hour play doesn’t fill in all the blanks or promise a happy ending. It’s a smart, thought-provoking and quite moving play with much to say to those who listen.